The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
For electric vehicles, refrigeration systems (especially heat pump systems) need to provide cabin climate control and powertrain cooling (e.g., cooling of a battery pack, power electronics and/or other electronic components). In the winter (or during cold temperature conditions), a cabin condenser can be required to condense refrigerant at least at 40° C. in order to supply warm enough air for cabin heating. If refrigerant is at a temperature less than 40° C., then the cabin condenser may not output enough heat to satisfy cabin heating requests. If, while the cabin condenser is being used to supply warm air, there is a need to use an outside condenser for powertrain cooling purposes, almost all heating capacity of the refrigeration system is provided at the outside condenser. This is because the outside condenser is much bigger than the cabin condenser. Also, rate of air flow through the outside condenser is much higher than a rate of air flow through the cabin condenser. As a result, the refrigeration system is unable to provide cabin comfort (i.e., adjust an air temperature in the cabin to a set temperature while providing power train cooling.